Renee Coleman-Mitchell, Connecticut’s public health commissioner, said Tuesday that she has no plans to release the most recent round of statewide school-by-school immunization data, despite calls this week from lawmakers who say parents should have access to the information as the school year begins.

“In Connecticut, we have only had three measles cases so far in 2019 and the last case was in April,” Coleman-Mitchell said in a prepared statement to the CT Mirror. “Given that we have not had any further measles cases since April and because the immunization rate for the measles, mumps, and rubella vaccines in Connecticut remains above 95 percent statewide, we will not be releasing immunization rates by school for the 2018-2019 school year at this time.”

The commissioner said the department would disclose county-level immunization data, which has been common practice, in October.

In May, Coleman-Mitchell made public for the first time a school-by-school assessment of child immunization rates. The figures – from the 2017-18 school year – showed 102 institutions where fewer than 95 percent of kindergarten students were vaccinated against measles, mumps and rubella, which is the threshold recommended by the Centers for Disease Control and Prevention.

Following the release, legislators said they expected another batch of data to be disclosed – this time for 2018-19 year. But a Bristol couple sued the health department, seeking an injunction to halt the publication of those numbers and requesting the removal of the 2017-18 figures from a state website. The case is pending.

Coleman-Mitchell has claimed that state law and departmental regulations give her broad powers to decide whether to release the school-by-school data. It was not immediately clear why she declined to release the newest round of numbers. A spokeswoman for the commissioner did not immediately return calls seeking comment Tuesday.

Senate Majority Leader Bob Duff, D-Norwalk, said he would reach out to the commissioner to learn more about why the department is withholding the data.

“I do believe that transparency is good in this instance,” he said. “When the data was released last spring, what we saw with the trends was fewer and fewer kids were getting vaccinated. And there was an increase in the religious exemption, so that shows we should be taking a look at that exemption.”

After the last disclosure of school-by-school figures, Gov. Ned Lamont said: “This data is startling and needs to be addressed. This cannot become a public health crisis as we have seen in other states. Making sure all of our young students in Connecticut are safe is the No. 1 priority.”

A spokesman for Lamont did not return calls seeking comment Tuesday.

On Monday, lawmakers called on Coleman-Mitchell to release the latest statistics as children in some districts reported for the first day of school. Other districts are expected to start later this week.

House Majority Leader Matthew Ritter, D-Hartford, the state would be “negligent” if it withheld data that showed an increase in vaccine exemptions.

“If the number of people claiming religious exemptions is higher than the previous school year, DPH would be negligent not to release that information,” he said. “I think the state is susceptible to another lawsuit if someone comes down with measles.”

Rep. Liz Linehan, D-Cheshire, said the data would let parents – especially those with immunocompromised children – know what percentage of kids at schools are unvaccinated.

“This is about transparency and it’s about providing parents with the appropriate information they need to keep their kids safe and so they can make an educated decision,” she said.

The latest dispute over the data release could force a law change. Ritter said legislators will likely move to include new language in state law that mandates the health department release vaccination rates by school.

“As we look at changing the laws around vaccinations in our state, if DPH is not willing to release the data, then we could also change the law to make sure it’s really clear that it should be released,” he said.